Vildagliptin is used for type 2 or non-insulin dependent diabetes. It increases the amount of insulin produced by the body. It also decreases the amount of glucagon which is produced by the body. Because of these effects, vildagliptin can help to control blood sugar levels in people with diabetes. Vildagliptin is used in combination with other medicines which help to control blood sugar levels.
DPP-IV inhibitors work by blocking the action of DPP-IV, an enzyme which destroys the hormone incretin. There are two types of incretin hormones found in the body, called glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP). These hormones are naturally produced by the body in response to food intake. Their function is to help the body produce more insulin only when it is needed and reduce the amount of glucose being produced by the liver when it is not needed. Vildagliptin works by binding to DPP-IV and preventing it from breaking down the GLP-1 and GIP. This increases the levels of these hormones in the body and so increases their effect on controlling blood sugar.

Its chemical name is (S)-{[(3-hydroxyadamantan-1-yl)amino]acetyl}pyrrolidine-2-carbonitril and its chemical structure is shown in the Formula I.
Vildagliptin is marketed under the trademark Galvus® in 50 mg dosage forms by NOVARTIS. It is used against diabetes mellitus, but particularly in treating type 2 diabetes. Galvus® includes lactose anhydrose, microcrystalline cellulose, sodium starch glycolate and magnesium stearate.
In currently commercially available dose of vildagliptin formulation, microcrystalline cellulose is used as a diluent. In contrast, in this present invention, dibasic calcium phosphate was used as a diluent to achieve improved compression and flowability in the formulation.
There are various patents and applications available in the patent literature in relation to vildagliptin formulations. In the patent application EP1841413A2 and EP2165703A3, direct compression is used to develop tablet formulation of DPP-IV inhibitor compounds, especially vildagliptin or an acid addition salt thereof.
It is known that DPP-IV inhibitors with primary or secondary amino group show incompatibilities, degradation problems or extraction problems with some excipients especially excipients that have acidic properties. Vildagliptin has also a secondary amino group on its chemical structure. In solid dosage forms, it may react with many excipients or impurities of excipients, although vildagliptin itself is very stable.
In this invention, diluent is used in a specific ratio in order to achieve desired release profile with desired tablet weight and desired flow during the process. Dibasic calcium phosphate has been chosen as a diluent to achieve high stability in the solid dosage form of vildagliptin.